Hypodermic needle



2 Nov. 25, 1941; EVERETT 2,263,692

HYPODERMIC NEEDLE F'iied March so; 1938 Patented Nov. 25, 1941 HYPODERMIC NEEDLE Samuel James Everett, Thornton Heath, England Application March 30, 1938, Serial No. 198,961 In Great Britain December 7, 1937 1 Claim.

This invention concerns improvements relating to hypodermic needles and has for its principal object to reduce the dangers of accidental breakage of such needles during their insertion in the body and during injections.

The part of a broken needle left in the body is frequently difficult to locate and difficult to extract. Unless the said part is extracted, however, it is likely to travel in the body and this is extremely dangerous. In fact, fatalities have occurred due to the breakage of hypodermic needles near vital organs. It is a particular object of the invention to obviate these dangers as far as possible.

One specific object of the invention is to provide means for the easy extraction of a broken needle part or, at least, for its easy location.

According to the 'present invention, a hypodermic needle device is provided with a safety wire or wires extending along the outside of the needle and attached to it within its effective length in such fashion as to be capable of penetrating the tissues together with the said needle. By the effective length of the needle is meant that part of its length which can be inserted in the body.

Such a safety wire may be provided primarily for various purposes: A fine wire attached to the needle towards its point and extending to the needle mount furnishes means for the easy extraction of a broken needle part, or at least for its easy location, whether breakage has occurred at or near the bottom of the mount or at a point beneath the skin. To avoid danger of the wire itself breaking, it should be made of a soft material of high tensile strength and should preferably be attached to the needle towards the point and at or near the mount only.

Various embodiments of the invention by way of example will now be described with reference to the accompanying drawing, in which:

Fig. 1 is an elevation of a hypodermic needle,

Fig. 2 is a cross-section at 11-11 in Fig. 1,

Fig. 3 an elevation, at right angles to Fig. 1, showing a modified needle and a stop-device,

Fig. 4 a cross-section at IV--IV in Fig. 3,

Fig. 5 a side elevation of a needle having a safety wire with its end toward the needle point pared down to the needle and having and alternative form of stop-device, and

Fig. 6 a view of the stop-device of Fig. 5 removed from the needle.

Referring to the drawing, the needle proper l is secured in a mount 2 of any convenient or known type, for example, a mount as described 55 mount.

in the specification of my United States Patent application Serial No. 194,941. The mount illustrated .has a tapered bore 3 intended to be removably fitted over a nozzle-shaped part on a syringe.

According to the invention, a length of wire 4 is attached to the outside of the needle I. This wire should be made of soft material of great tensile strength, for example an alloy consisting of nickel and 25% copper. For practical reasons, the diameter of the wire should not exceed the diameter of the needle and it should preferably be much smaller, say A; the diameter of the needle. If desired, the wire may be of a shaped cross-section. for example, roundshaped. Alternatively two or more wires may be used.

As illustrated, the needle is sharpened by being cut off at an angle making a sharp point at one side and an inclined end portion. The wire is practically as long as the needle and is attached, for instance soldered. to the latter near the point, that is at 5. The extreme end of the wire preferably extends to a position opposite the inclined end portion of the needle close to the needle point (Fig. 5). Where the lower end of the wire 4 is attached to the needle, it is pared down to the surface of the said needle so as to run smoothly into or blend with the latter, as indicated at H (Figs. 3 and 5). This may be conveniently provided for by pointing the wire before its attachment. The upper end of the wire is attached to the needle immediately below the mount 2, that is at 6. It is preferred to attach the wire to the needle at the ends only, since it can then flex independently of the needle and is thus less liable to be broken itself.

Fig. 3 shows a mount similar to that shown in Fig. 1, but differing in having a substantially cylindrical nipple-portion 1. Fitted over this nippie-portion is a small stop-sleeve 8 of, say, brass or nickel-silver. The sleeve 8 is preferably simply slipped or sprung over the nipple portion of the mount, but it may be soldered thereon. It may consist of a length of solid drawn tube or jointed tube with a closed or an open joint. If desired, the tube may be constricted at or near its lower end to contact with or grip the needle. For example, it may be formed with three dents spaced around its lower part.

The sleeve forms a stop which prevents the needle being inserted in the body tissues beyond a certain depth. Should the needle break, it is most likely that the fracture will be close to the Consequently there will then be a pro jecting length of needle which can be easily gripped for extracting the part left in the body. Should the needle break just above the surface of the body, it can still be easily extracted by pulling on the wire 4 or, at least, travel of the needle can be prevented until it is extracted. If the needle breaks below the surface, the wire may serve to lead the surgeon to the precise location of the broken part.

Another form of stop, shown in Figs. 5 and 6, takes the form of a strip 9 of springy metal having two holes I0 towards its ends. Held in a bowshape, the strip can be slipped over the needle I to a desired position in which it becomes secured, when the bow is released, due to its tendency to straighten. At least the lower hole I0 is adapted for gripping the needle firmly. As shown, both holes l0 are formed as half-round holes with wedge-shaped portions extending towards the respectively nearer ends of the strip 9. These wedge-shaped portions assist in gripping the needle firmly. Furthermore, the grip is. accentuated if pressure is applied to the lower end of the stop, for instance when the needle is inserted in the body and the said end comes in contact with its surface. Also such a stop can even be used for pulling out a needle which has broken near the mount. The width of the strip 9 may conveniently be about ten times the diameter of the needle and its length is about 4''.

Various departures may be made from the simple form of stop means shown in Figs. 5 and 6: The strip may be more conveniently shaped for producing the necessary spring-efiect and may be provided with projecting parts to facilitate adjustment.

I claim:

A hypodermic needle comprising a hollow tube of substantially circular cross section, one end of said needle being connected to a mount, the free end of the needle being cut ofi at an angle forming a sharp point at one side and an inclined end portion. extending backwardly from the point to the opposite side from said point, and a wire ex:

tending along the point side of said needle from a position near said mount to a position near said point and terminating opposite the inclined end portion of the needle where the needle is of less thickness than at its full tubular section, the ends of said wire being metallically secured to the needle and its intermediate portion. being free so as to be able to flex independently of the needle; and the end of the wire toward the point, of the needle being pared down tothe needle surface.

SAMUEL JAMES EVERETT. 

